Badenes-Perez, F.R., Zalom, F.G., & Bentley, W.J. 2002 Are San José scale (Hom., Diaspididae) pheromone trap captures predictive of crawler densities?. Journal of Applied Entomology 126(10): 545-549.
Notes: Abundance of San José scale (SJS), Quadraspidiotus perniciosus (Comstock), adult males and crawlers were monitored with pheromone traps checked weekly and associated sticky tape traps monitored biweekly, respectively, in commercial almond orchards in Kern County, California, USA, during 1999 and 2000. Regression analysis was used to determine if SJS crawler abundance could be predicted from SJS males captured on pheromone traps. No significant relationship ( P > 0.05) was indicated for any generation or for all SJS captured for the season in 1999. With greater replication in 2000, statistically significant relationships were indicated for the first generation (r = 0.727; F = 25.712; P < 0.0001; n = 25) and for all generations (r = 0.777; F = 63.239; P < 0.0001; n = 25). An additional orchard in 2000 was divided into 18 1.21-ha plots with different treatments applied. A statistically significant relationship was indicated for the first generation (r = 0.507; F = 11.769; P = 0.0016; n = 36) and second generation (r = 0.436; F = 7.972; p = 0.0079; n = 36). These results suggest that relative densities of SJS crawlers on sticky tapes can be estimated using SJS male trap captures for the first generation, and that this approximation is appropriate for whole orchards or for subplots within orchards as small as 1.21-ha.